Patent · US Expired

Method and apparatus for controlling measurement in a spectrophotometer

US4545681A · kind A · utility

2Cited by
2References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 9, 1983
Grant dateOct 8, 1985
Priority date
Expiry dateFeb 9, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2201/127
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

In a spectrophotometer of double beam type using automatic gain control, preparatory scanning is first carried out by scanning reference and sample cells with radiation of varying wavelengths both in an empty state, and controlling the gain of a photo detector at each wavelength such that a detector output responding to a sample cell transmitted beam may become constant while storing a detector output responding to a reference cell transmitted beam. Measurement of a sample material is then carried out at each wavelength by scanning the reference cell and the sample material-charged sample cell, reading out the reference output stored in the preparatory scanning stage as a reference voltage, and controlling the gain of the detector such that a detector output responding to a reference cell transmitted beam may be equal to the reference voltage.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.